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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /drivers/spi/spi-mxs.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip
Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted
Pull networking updates from Jakub Kicinski: "Core: - Add dedicated kmem_cache for typical/small skb->head, avoid having to access struct page at kfree time, and improve memory use. - Introduce sysctl to set default RPS configuration for new netdevs. - Define Netlink protocol specification format which can be used to describe messages used by each family and auto-generate parsers. Add tools for generating kernel data structures and uAPI headers. - Expose all net/core sysctls inside netns. - Remove 4s sleep in netpoll if carrier is instantly detected on boot. - Add configurable limit of MDB entries per port, and port-vlan. - Continue populating drop reasons throughout the stack. - Retire a handful of legacy Qdiscs and classifiers. Protocols: - Support IPv4 big TCP (TSO frames larger than 64kB). - Add IP_LOCAL_PORT_RANGE socket option, to control local port range on socket by socket basis. - Track and report in procfs number of MPTCP sockets used. - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path manager. - IPv6: don't check net.ipv6.route.max_size and rely on garbage collection to free memory (similarly to IPv4). - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986). - ICMP: add per-rate limit counters. - Add support for user scanning requests in ieee802154. - Remove static WEP support. - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate reporting. - WiFi 7 EHT channel puncturing support (client & AP). BPF: - Add a rbtree data structure following the "next-gen data structure" precedent set by recently added linked list, that is, by using kfunc + kptr instead of adding a new BPF map type. - Expose XDP hints via kfuncs with initial support for RX hash and timestamp metadata. - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to better support decap on GRE tunnel devices not operating in collect metadata. - Improve x86 JIT's codegen for PROBE_MEM runtime error checks. - Remove the need for trace_printk_lock for bpf_trace_printk and bpf_trace_vprintk helpers. - Extend libbpf's bpf_tracing.h support for tracing arguments of kprobes/uprobes and syscall as a special case. - Significantly reduce the search time for module symbols by livepatch and BPF. - Enable cpumasks to be used as kptrs, which is useful for tracing programs tracking which tasks end up running on which CPUs in different time intervals. - Add support for BPF trampoline on s390x and riscv64. - Add capability to export the XDP features supported by the NIC. - Add __bpf_kfunc tag for marking kernel functions as kfuncs. - Add cgroup.memory=nobpf kernel parameter option to disable BPF memory accounting for container environments. Netfilter: - Remove the CLUSTERIP target. It has been marked as obsolete for years, and we still have WARN splats wrt races of the out-of-band /proc interface installed by this target. - Add 'destroy' commands to nf_tables. They are identical to the existing 'delete' commands, but do not return an error if the referenced object (set, chain, rule...) did not exist. Driver API: - Improve cpumask_local_spread() locality to help NICs set the right IRQ affinity on AMD platforms. - Separate C22 and C45 MDIO bus transactions more clearly. - Introduce new DCB table to control DSCP rewrite on egress. - Support configuration of Physical Layer Collision Avoidance (PLCA) Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of shared medium Ethernet. - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing preemption of low priority frames by high priority frames. - Add support for controlling MACSec offload using netlink SET. - Rework devlink instance refcounts to allow registration and de-registration under the instance lock. Split the code into multiple files, drop some of the unnecessarily granular locks and factor out common parts of netlink operation handling. - Add TX frame aggregation parameters (for USB drivers). - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning messages with notifications for debug. - Allow offloading of UDP NEW connections via act_ct. - Add support for per action HW stats in TC. - Support hardware miss to TC action (continue processing in SW from a specific point in the action chain). - Warn if old Wireless Extension user space interface is used with modern cfg80211/mac80211 drivers. Do not support Wireless Extensions for Wi-Fi 7 devices at all. Everyone should switch to using nl80211 interface instead. - Improve the CAN bit timing configuration. Use extack to return error messages directly to user space, update the SJW handling, including the definition of a new default value that will benefit CAN-FD controllers, by increasing their oscillator tolerance. New hardware / drivers: - Ethernet: - nVidia BlueField-3 support (control traffic driver) - Ethernet support for imx93 SoCs - Motorcomm yt8531 gigabit Ethernet PHY - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA) - Microchip LAN8841 PHY (incl. cable diagnostics and PTP) - Amlogic gxl MDIO mux - WiFi: - RealTek RTL8188EU (rtl8xxxu) - Qualcomm Wi-Fi 7 devices (ath12k) - CAN: - Renesas R-Car V4H Drivers: - Bluetooth: - Set Per Platform Antenna Gain (PPAG) for Intel controllers. - Ethernet NICs: - Intel (1G, igc): - support TSN / Qbv / packet scheduling features of i226 model - Intel (100G, ice): - use GNSS subsystem instead of TTY - multi-buffer XDP support - extend support for GPIO pins to E823 devices - nVidia/Mellanox: - update the shared buffer configuration on PFC commands - implement PTP adjphase function for HW offset control - TC support for Geneve and GRE with VF tunnel offload - more efficient crypto key management method - multi-port eswitch support - Netronome/Corigine: - add DCB IEEE support - support IPsec offloading for NFP3800 - Freescale/NXP (enetc): - support XDP_REDIRECT for XDP non-linear buffers - improve reconfig, avoid link flap and waiting for idle - support MAC Merge layer - Other NICs: - sfc/ef100: add basic devlink support for ef100 - ionic: rx_push mode operation (writing descriptors via MMIO) - bnxt: use the auxiliary bus abstraction for RDMA - r8169: disable ASPM and reset bus in case of tx timeout - cpsw: support QSGMII mode for J721e CPSW9G - cpts: support pulse-per-second output - ngbe: add an mdio bus driver - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing - r8152: handle devices with FW with NCM support - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation - virtio-net: support multi buffer XDP - virtio/vsock: replace virtio_vsock_pkt with sk_buff - tsnep: XDP support - Ethernet high-speed switches: - nVidia/Mellanox (mlxsw): - add support for latency TLV (in FW control messages) - Microchip (sparx5): - separate explicit and implicit traffic forwarding rules, make the implicit rules always active - add support for egress DSCP rewrite - IS0 VCAP support (Ingress Classification) - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS etc.) - ES2 VCAP support (Egress Access Control) - support for Per-Stream Filtering and Policing (802.1Q, 8.6.5.1) - Ethernet embedded switches: - Marvell (mv88e6xxx): - add MAB (port auth) offload support - enable PTP receive for mv88e6390 - NXP (ocelot): - support MAC Merge layer - support for the the vsc7512 internal copper phys - Microchip: - lan9303: convert to PHYLINK - lan966x: support TC flower filter statistics - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x - lan937x: support Credit Based Shaper configuration - ksz9477: support Energy Efficient Ethernet - other: - qca8k: convert to regmap read/write API, use bulk operations - rswitch: Improve TX timestamp accuracy - Intel WiFi (iwlwifi): - EHT (Wi-Fi 7) rate reporting - STEP equalizer support: transfer some STEP (connection to radio on platforms with integrated wifi) related parameters from the BIOS to the firmware. - Qualcomm 802.11ax WiFi (ath11k): - IPQ5018 support - Fine Timing Measurement (FTM) responder role support - channel 177 support - MediaTek WiFi (mt76): - per-PHY LED support - mt7996: EHT (Wi-Fi 7) support - Wireless Ethernet Dispatch (WED) reset support - switch to using page pool allocator - RealTek WiFi (rtw89): - support new version of Bluetooth co-existance - Mobile: - rmnet: support TX aggregation" * tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits) page_pool: add a comment explaining the fragment counter usage net: ethtool: fix __ethtool_dev_mm_supported() implementation ethtool: pse-pd: Fix double word in comments xsk: add linux/vmalloc.h to xsk.c sefltests: netdevsim: wait for devlink instance after netns removal selftest: fib_tests: Always cleanup before exit net/mlx5e: Align IPsec ASO result memory to be as required by hardware net/mlx5e: TC, Set CT miss to the specific ct action instance net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG net/mlx5: Refactor tc miss handling to a single function net/mlx5: Kconfig: Make tc offload depend on tc skb extension net/sched: flower: Support hardware miss to tc action net/sched: flower: Move filter handle initialization earlier net/sched: cls_api: Support hardware miss to tc action net/sched: Rename user cookie and act cookie sfc: fix builds without CONFIG_RTC_LIB sfc: clean up some inconsistent indentings net/mlx4_en: Introduce flexible array to silence overflow warning net: lan966x: Fix possible deadlock inside PTP net/ulp: Remove redundant ->clone() test in inet_clone_ulp(). ...
Diffstat (limited to 'drivers/spi/spi-mxs.c')
-rw-r--r--drivers/spi/spi-mxs.c675
1 files changed, 675 insertions, 0 deletions
diff --git a/drivers/spi/spi-mxs.c b/drivers/spi/spi-mxs.c
new file mode 100644
index 000000000..55178579f
--- /dev/null
+++ b/drivers/spi/spi-mxs.c
@@ -0,0 +1,675 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Freescale MXS SPI master driver
+//
+// Copyright 2012 DENX Software Engineering, GmbH.
+// Copyright 2012 Freescale Semiconductor, Inc.
+// Copyright 2008 Embedded Alley Solutions, Inc All Rights Reserved.
+//
+// Rework and transition to new API by:
+// Marek Vasut <marex@denx.de>
+//
+// Based on previous attempt by:
+// Fabio Estevam <fabio.estevam@freescale.com>
+//
+// Based on code from U-Boot bootloader by:
+// Marek Vasut <marex@denx.de>
+//
+// Based on spi-stmp.c, which is:
+// Author: Dmitry Pervushin <dimka@embeddedalley.com>
+
+#include <linux/kernel.h>
+#include <linux/ioport.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/dma-mapping.h>
+#include <linux/dmaengine.h>
+#include <linux/highmem.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/completion.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
+#include <linux/module.h>
+#include <linux/stmp_device.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/mxs-spi.h>
+#include <trace/events/spi.h>
+
+#define DRIVER_NAME "mxs-spi"
+
+/* Use 10S timeout for very long transfers, it should suffice. */
+#define SSP_TIMEOUT 10000
+
+#define SG_MAXLEN 0xff00
+
+/*
+ * Flags for txrx functions. More efficient that using an argument register for
+ * each one.
+ */
+#define TXRX_WRITE (1<<0) /* This is a write */
+#define TXRX_DEASSERT_CS (1<<1) /* De-assert CS at end of txrx */
+
+struct mxs_spi {
+ struct mxs_ssp ssp;
+ struct completion c;
+ unsigned int sck; /* Rate requested (vs actual) */
+};
+
+static int mxs_spi_setup_transfer(struct spi_device *dev,
+ const struct spi_transfer *t)
+{
+ struct mxs_spi *spi = spi_master_get_devdata(dev->master);
+ struct mxs_ssp *ssp = &spi->ssp;
+ const unsigned int hz = min(dev->max_speed_hz, t->speed_hz);
+
+ if (hz == 0) {
+ dev_err(&dev->dev, "SPI clock rate of zero not allowed\n");
+ return -EINVAL;
+ }
+
+ if (hz != spi->sck) {
+ mxs_ssp_set_clk_rate(ssp, hz);
+ /*
+ * Save requested rate, hz, rather than the actual rate,
+ * ssp->clk_rate. Otherwise we would set the rate every transfer
+ * when the actual rate is not quite the same as requested rate.
+ */
+ spi->sck = hz;
+ /*
+ * Perhaps we should return an error if the actual clock is
+ * nowhere close to what was requested?
+ */
+ }
+
+ writel(BM_SSP_CTRL0_LOCK_CS,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+
+ writel(BF_SSP_CTRL1_SSP_MODE(BV_SSP_CTRL1_SSP_MODE__SPI) |
+ BF_SSP_CTRL1_WORD_LENGTH(BV_SSP_CTRL1_WORD_LENGTH__EIGHT_BITS) |
+ ((dev->mode & SPI_CPOL) ? BM_SSP_CTRL1_POLARITY : 0) |
+ ((dev->mode & SPI_CPHA) ? BM_SSP_CTRL1_PHASE : 0),
+ ssp->base + HW_SSP_CTRL1(ssp));
+
+ writel(0x0, ssp->base + HW_SSP_CMD0);
+ writel(0x0, ssp->base + HW_SSP_CMD1);
+
+ return 0;
+}
+
+static u32 mxs_spi_cs_to_reg(unsigned cs)
+{
+ u32 select = 0;
+
+ /*
+ * i.MX28 Datasheet: 17.10.1: HW_SSP_CTRL0
+ *
+ * The bits BM_SSP_CTRL0_WAIT_FOR_CMD and BM_SSP_CTRL0_WAIT_FOR_IRQ
+ * in HW_SSP_CTRL0 register do have multiple usage, please refer to
+ * the datasheet for further details. In SPI mode, they are used to
+ * toggle the chip-select lines (nCS pins).
+ */
+ if (cs & 1)
+ select |= BM_SSP_CTRL0_WAIT_FOR_CMD;
+ if (cs & 2)
+ select |= BM_SSP_CTRL0_WAIT_FOR_IRQ;
+
+ return select;
+}
+
+static int mxs_ssp_wait(struct mxs_spi *spi, int offset, int mask, bool set)
+{
+ const unsigned long timeout = jiffies + msecs_to_jiffies(SSP_TIMEOUT);
+ struct mxs_ssp *ssp = &spi->ssp;
+ u32 reg;
+
+ do {
+ reg = readl_relaxed(ssp->base + offset);
+
+ if (!set)
+ reg = ~reg;
+
+ reg &= mask;
+
+ if (reg == mask)
+ return 0;
+ } while (time_before(jiffies, timeout));
+
+ return -ETIMEDOUT;
+}
+
+static void mxs_ssp_dma_irq_callback(void *param)
+{
+ struct mxs_spi *spi = param;
+
+ complete(&spi->c);
+}
+
+static irqreturn_t mxs_ssp_irq_handler(int irq, void *dev_id)
+{
+ struct mxs_ssp *ssp = dev_id;
+
+ dev_err(ssp->dev, "%s[%i] CTRL1=%08x STATUS=%08x\n",
+ __func__, __LINE__,
+ readl(ssp->base + HW_SSP_CTRL1(ssp)),
+ readl(ssp->base + HW_SSP_STATUS(ssp)));
+ return IRQ_HANDLED;
+}
+
+static int mxs_spi_txrx_dma(struct mxs_spi *spi,
+ unsigned char *buf, int len,
+ unsigned int flags)
+{
+ struct mxs_ssp *ssp = &spi->ssp;
+ struct dma_async_tx_descriptor *desc = NULL;
+ const bool vmalloced_buf = is_vmalloc_addr(buf);
+ const int desc_len = vmalloced_buf ? PAGE_SIZE : SG_MAXLEN;
+ const int sgs = DIV_ROUND_UP(len, desc_len);
+ int sg_count;
+ int min, ret;
+ u32 ctrl0;
+ struct page *vm_page;
+ struct {
+ u32 pio[4];
+ struct scatterlist sg;
+ } *dma_xfer;
+
+ if (!len)
+ return -EINVAL;
+
+ dma_xfer = kcalloc(sgs, sizeof(*dma_xfer), GFP_KERNEL);
+ if (!dma_xfer)
+ return -ENOMEM;
+
+ reinit_completion(&spi->c);
+
+ /* Chip select was already programmed into CTRL0 */
+ ctrl0 = readl(ssp->base + HW_SSP_CTRL0);
+ ctrl0 &= ~(BM_SSP_CTRL0_XFER_COUNT | BM_SSP_CTRL0_IGNORE_CRC |
+ BM_SSP_CTRL0_READ);
+ ctrl0 |= BM_SSP_CTRL0_DATA_XFER;
+
+ if (!(flags & TXRX_WRITE))
+ ctrl0 |= BM_SSP_CTRL0_READ;
+
+ /* Queue the DMA data transfer. */
+ for (sg_count = 0; sg_count < sgs; sg_count++) {
+ /* Prepare the transfer descriptor. */
+ min = min(len, desc_len);
+
+ /*
+ * De-assert CS on last segment if flag is set (i.e., no more
+ * transfers will follow)
+ */
+ if ((sg_count + 1 == sgs) && (flags & TXRX_DEASSERT_CS))
+ ctrl0 |= BM_SSP_CTRL0_IGNORE_CRC;
+
+ if (ssp->devid == IMX23_SSP) {
+ ctrl0 &= ~BM_SSP_CTRL0_XFER_COUNT;
+ ctrl0 |= min;
+ }
+
+ dma_xfer[sg_count].pio[0] = ctrl0;
+ dma_xfer[sg_count].pio[3] = min;
+
+ if (vmalloced_buf) {
+ vm_page = vmalloc_to_page(buf);
+ if (!vm_page) {
+ ret = -ENOMEM;
+ goto err_vmalloc;
+ }
+
+ sg_init_table(&dma_xfer[sg_count].sg, 1);
+ sg_set_page(&dma_xfer[sg_count].sg, vm_page,
+ min, offset_in_page(buf));
+ } else {
+ sg_init_one(&dma_xfer[sg_count].sg, buf, min);
+ }
+
+ ret = dma_map_sg(ssp->dev, &dma_xfer[sg_count].sg, 1,
+ (flags & TXRX_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+
+ len -= min;
+ buf += min;
+
+ /* Queue the PIO register write transfer. */
+ desc = dmaengine_prep_slave_sg(ssp->dmach,
+ (struct scatterlist *)dma_xfer[sg_count].pio,
+ (ssp->devid == IMX23_SSP) ? 1 : 4,
+ DMA_TRANS_NONE,
+ sg_count ? DMA_PREP_INTERRUPT : 0);
+ if (!desc) {
+ dev_err(ssp->dev,
+ "Failed to get PIO reg. write descriptor.\n");
+ ret = -EINVAL;
+ goto err_mapped;
+ }
+
+ desc = dmaengine_prep_slave_sg(ssp->dmach,
+ &dma_xfer[sg_count].sg, 1,
+ (flags & TXRX_WRITE) ? DMA_MEM_TO_DEV : DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
+
+ if (!desc) {
+ dev_err(ssp->dev,
+ "Failed to get DMA data write descriptor.\n");
+ ret = -EINVAL;
+ goto err_mapped;
+ }
+ }
+
+ /*
+ * The last descriptor must have this callback,
+ * to finish the DMA transaction.
+ */
+ desc->callback = mxs_ssp_dma_irq_callback;
+ desc->callback_param = spi;
+
+ /* Start the transfer. */
+ dmaengine_submit(desc);
+ dma_async_issue_pending(ssp->dmach);
+
+ if (!wait_for_completion_timeout(&spi->c,
+ msecs_to_jiffies(SSP_TIMEOUT))) {
+ dev_err(ssp->dev, "DMA transfer timeout\n");
+ ret = -ETIMEDOUT;
+ dmaengine_terminate_all(ssp->dmach);
+ goto err_vmalloc;
+ }
+
+ ret = 0;
+
+err_vmalloc:
+ while (--sg_count >= 0) {
+err_mapped:
+ dma_unmap_sg(ssp->dev, &dma_xfer[sg_count].sg, 1,
+ (flags & TXRX_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE);
+ }
+
+ kfree(dma_xfer);
+
+ return ret;
+}
+
+static int mxs_spi_txrx_pio(struct mxs_spi *spi,
+ unsigned char *buf, int len,
+ unsigned int flags)
+{
+ struct mxs_ssp *ssp = &spi->ssp;
+
+ writel(BM_SSP_CTRL0_IGNORE_CRC,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
+
+ while (len--) {
+ if (len == 0 && (flags & TXRX_DEASSERT_CS))
+ writel(BM_SSP_CTRL0_IGNORE_CRC,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+
+ if (ssp->devid == IMX23_SSP) {
+ writel(BM_SSP_CTRL0_XFER_COUNT,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
+ writel(1,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+ } else {
+ writel(1, ssp->base + HW_SSP_XFER_SIZE);
+ }
+
+ if (flags & TXRX_WRITE)
+ writel(BM_SSP_CTRL0_READ,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
+ else
+ writel(BM_SSP_CTRL0_READ,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+
+ writel(BM_SSP_CTRL0_RUN,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+
+ if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 1))
+ return -ETIMEDOUT;
+
+ if (flags & TXRX_WRITE)
+ writel(*buf, ssp->base + HW_SSP_DATA(ssp));
+
+ writel(BM_SSP_CTRL0_DATA_XFER,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+
+ if (!(flags & TXRX_WRITE)) {
+ if (mxs_ssp_wait(spi, HW_SSP_STATUS(ssp),
+ BM_SSP_STATUS_FIFO_EMPTY, 0))
+ return -ETIMEDOUT;
+
+ *buf = (readl(ssp->base + HW_SSP_DATA(ssp)) & 0xff);
+ }
+
+ if (mxs_ssp_wait(spi, HW_SSP_CTRL0, BM_SSP_CTRL0_RUN, 0))
+ return -ETIMEDOUT;
+
+ buf++;
+ }
+
+ if (len <= 0)
+ return 0;
+
+ return -ETIMEDOUT;
+}
+
+static int mxs_spi_transfer_one(struct spi_master *master,
+ struct spi_message *m)
+{
+ struct mxs_spi *spi = spi_master_get_devdata(master);
+ struct mxs_ssp *ssp = &spi->ssp;
+ struct spi_transfer *t;
+ unsigned int flag;
+ int status = 0;
+
+ /* Program CS register bits here, it will be used for all transfers. */
+ writel(BM_SSP_CTRL0_WAIT_FOR_CMD | BM_SSP_CTRL0_WAIT_FOR_IRQ,
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_CLR);
+ writel(mxs_spi_cs_to_reg(m->spi->chip_select),
+ ssp->base + HW_SSP_CTRL0 + STMP_OFFSET_REG_SET);
+
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+
+ trace_spi_transfer_start(m, t);
+
+ status = mxs_spi_setup_transfer(m->spi, t);
+ if (status)
+ break;
+
+ /* De-assert on last transfer, inverted by cs_change flag */
+ flag = (&t->transfer_list == m->transfers.prev) ^ t->cs_change ?
+ TXRX_DEASSERT_CS : 0;
+
+ /*
+ * Small blocks can be transfered via PIO.
+ * Measured by empiric means:
+ *
+ * dd if=/dev/mtdblock0 of=/dev/null bs=1024k count=1
+ *
+ * DMA only: 2.164808 seconds, 473.0KB/s
+ * Combined: 1.676276 seconds, 610.9KB/s
+ */
+ if (t->len < 32) {
+ writel(BM_SSP_CTRL1_DMA_ENABLE,
+ ssp->base + HW_SSP_CTRL1(ssp) +
+ STMP_OFFSET_REG_CLR);
+
+ if (t->tx_buf)
+ status = mxs_spi_txrx_pio(spi,
+ (void *)t->tx_buf,
+ t->len, flag | TXRX_WRITE);
+ if (t->rx_buf)
+ status = mxs_spi_txrx_pio(spi,
+ t->rx_buf, t->len,
+ flag);
+ } else {
+ writel(BM_SSP_CTRL1_DMA_ENABLE,
+ ssp->base + HW_SSP_CTRL1(ssp) +
+ STMP_OFFSET_REG_SET);
+
+ if (t->tx_buf)
+ status = mxs_spi_txrx_dma(spi,
+ (void *)t->tx_buf, t->len,
+ flag | TXRX_WRITE);
+ if (t->rx_buf)
+ status = mxs_spi_txrx_dma(spi,
+ t->rx_buf, t->len,
+ flag);
+ }
+
+ trace_spi_transfer_stop(m, t);
+
+ if (status) {
+ stmp_reset_block(ssp->base);
+ break;
+ }
+
+ m->actual_length += t->len;
+ }
+
+ m->status = status;
+ spi_finalize_current_message(master);
+
+ return status;
+}
+
+static int mxs_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct mxs_spi *spi = spi_master_get_devdata(master);
+ struct mxs_ssp *ssp = &spi->ssp;
+ int ret;
+
+ clk_disable_unprepare(ssp->clk);
+
+ ret = pinctrl_pm_select_idle_state(dev);
+ if (ret) {
+ int ret2 = clk_prepare_enable(ssp->clk);
+
+ if (ret2)
+ dev_warn(dev, "Failed to reenable clock after failing pinctrl request (pinctrl: %d, clk: %d)\n",
+ ret, ret2);
+ }
+
+ return ret;
+}
+
+static int mxs_spi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct mxs_spi *spi = spi_master_get_devdata(master);
+ struct mxs_ssp *ssp = &spi->ssp;
+ int ret;
+
+ ret = pinctrl_pm_select_default_state(dev);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(ssp->clk);
+ if (ret)
+ pinctrl_pm_select_idle_state(dev);
+
+ return ret;
+}
+
+static int __maybe_unused mxs_spi_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ int ret;
+
+ ret = spi_master_suspend(master);
+ if (ret)
+ return ret;
+
+ if (!pm_runtime_suspended(dev))
+ return mxs_spi_runtime_suspend(dev);
+ else
+ return 0;
+}
+
+static int __maybe_unused mxs_spi_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ int ret;
+
+ if (!pm_runtime_suspended(dev))
+ ret = mxs_spi_runtime_resume(dev);
+ else
+ ret = 0;
+ if (ret)
+ return ret;
+
+ ret = spi_master_resume(master);
+ if (ret < 0 && !pm_runtime_suspended(dev))
+ mxs_spi_runtime_suspend(dev);
+
+ return ret;
+}
+
+static const struct dev_pm_ops mxs_spi_pm = {
+ SET_RUNTIME_PM_OPS(mxs_spi_runtime_suspend,
+ mxs_spi_runtime_resume, NULL)
+ SET_SYSTEM_SLEEP_PM_OPS(mxs_spi_suspend, mxs_spi_resume)
+};
+
+static const struct of_device_id mxs_spi_dt_ids[] = {
+ { .compatible = "fsl,imx23-spi", .data = (void *) IMX23_SSP, },
+ { .compatible = "fsl,imx28-spi", .data = (void *) IMX28_SSP, },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mxs_spi_dt_ids);
+
+static int mxs_spi_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *of_id =
+ of_match_device(mxs_spi_dt_ids, &pdev->dev);
+ struct device_node *np = pdev->dev.of_node;
+ struct spi_master *master;
+ struct mxs_spi *spi;
+ struct mxs_ssp *ssp;
+ struct clk *clk;
+ void __iomem *base;
+ int devid, clk_freq;
+ int ret = 0, irq_err;
+
+ /*
+ * Default clock speed for the SPI core. 160MHz seems to
+ * work reasonably well with most SPI flashes, so use this
+ * as a default. Override with "clock-frequency" DT prop.
+ */
+ const int clk_freq_default = 160000000;
+
+ irq_err = platform_get_irq(pdev, 0);
+ if (irq_err < 0)
+ return irq_err;
+
+ base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(base))
+ return PTR_ERR(base);
+
+ clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(clk))
+ return PTR_ERR(clk);
+
+ devid = (enum mxs_ssp_id) of_id->data;
+ ret = of_property_read_u32(np, "clock-frequency",
+ &clk_freq);
+ if (ret)
+ clk_freq = clk_freq_default;
+
+ master = spi_alloc_master(&pdev->dev, sizeof(*spi));
+ if (!master)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, master);
+
+ master->transfer_one_message = mxs_spi_transfer_one;
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+ master->mode_bits = SPI_CPOL | SPI_CPHA;
+ master->num_chipselect = 3;
+ master->dev.of_node = np;
+ master->flags = SPI_MASTER_HALF_DUPLEX;
+ master->auto_runtime_pm = true;
+
+ spi = spi_master_get_devdata(master);
+ ssp = &spi->ssp;
+ ssp->dev = &pdev->dev;
+ ssp->clk = clk;
+ ssp->base = base;
+ ssp->devid = devid;
+
+ init_completion(&spi->c);
+
+ ret = devm_request_irq(&pdev->dev, irq_err, mxs_ssp_irq_handler, 0,
+ dev_name(&pdev->dev), ssp);
+ if (ret)
+ goto out_master_free;
+
+ ssp->dmach = dma_request_chan(&pdev->dev, "rx-tx");
+ if (IS_ERR(ssp->dmach)) {
+ dev_err(ssp->dev, "Failed to request DMA\n");
+ ret = PTR_ERR(ssp->dmach);
+ goto out_master_free;
+ }
+
+ pm_runtime_enable(ssp->dev);
+ if (!pm_runtime_enabled(ssp->dev)) {
+ ret = mxs_spi_runtime_resume(ssp->dev);
+ if (ret < 0) {
+ dev_err(ssp->dev, "runtime resume failed\n");
+ goto out_dma_release;
+ }
+ }
+
+ ret = pm_runtime_resume_and_get(ssp->dev);
+ if (ret < 0) {
+ dev_err(ssp->dev, "runtime_get_sync failed\n");
+ goto out_pm_runtime_disable;
+ }
+
+ clk_set_rate(ssp->clk, clk_freq);
+
+ ret = stmp_reset_block(ssp->base);
+ if (ret)
+ goto out_pm_runtime_put;
+
+ ret = devm_spi_register_master(&pdev->dev, master);
+ if (ret) {
+ dev_err(&pdev->dev, "Cannot register SPI master, %d\n", ret);
+ goto out_pm_runtime_put;
+ }
+
+ pm_runtime_put(ssp->dev);
+
+ return 0;
+
+out_pm_runtime_put:
+ pm_runtime_put(ssp->dev);
+out_pm_runtime_disable:
+ pm_runtime_disable(ssp->dev);
+out_dma_release:
+ dma_release_channel(ssp->dmach);
+out_master_free:
+ spi_master_put(master);
+ return ret;
+}
+
+static int mxs_spi_remove(struct platform_device *pdev)
+{
+ struct spi_master *master;
+ struct mxs_spi *spi;
+ struct mxs_ssp *ssp;
+
+ master = platform_get_drvdata(pdev);
+ spi = spi_master_get_devdata(master);
+ ssp = &spi->ssp;
+
+ pm_runtime_disable(&pdev->dev);
+ if (!pm_runtime_status_suspended(&pdev->dev))
+ mxs_spi_runtime_suspend(&pdev->dev);
+
+ dma_release_channel(ssp->dmach);
+
+ return 0;
+}
+
+static struct platform_driver mxs_spi_driver = {
+ .probe = mxs_spi_probe,
+ .remove = mxs_spi_remove,
+ .driver = {
+ .name = DRIVER_NAME,
+ .of_match_table = mxs_spi_dt_ids,
+ .pm = &mxs_spi_pm,
+ },
+};
+
+module_platform_driver(mxs_spi_driver);
+
+MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
+MODULE_DESCRIPTION("MXS SPI master driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mxs-spi");